The circumpolar stars in the northern sky above trees at Herbert Lake, Banff National Park. At left is Ursa Major and the Big Dipper; at right is the W of Cassiopeia; at centre is Polaris and Ursa Minor or the Little Dipper. A blue glow of twilight to the north, and some faint red and green bands of airglow tint the sky. This is a stack of four exposures for the trees, mean combined to smooth noise, and one exposure for the sky, all 30 seconds at f/2 with the Laowa 15mm lens, and Sony a7III at ISO 6400.
The unusual STEVE auroral arc across the northern sky at Bow Lake, Banff National Park, Alberta on the night of July 16-17, 2018. The more normal green auroral arc is lower across the northern horizon. But STEVE here appears more pink. The STEVE aurora was colourless to the eye but did show faint fast-moving rays, here blurred by the long exposure. They were moving east to west. The Big Dipper is at left. The lights are from Num-Ti-Jah Lodge. This is a single exposure for the sky and a mean-stacked blend of 3 exposures for the ground to smooth noise. All 15 seconds at f/2 with the Sigma 20mm Art lens and Nikon D750 at ISO 6400.
The Big Dipper over the iconic Castle Mountain in Banff National Park, Alberta, with a backdrop of a faint aurora in the northern sky. This was at 3 am on July 16, 2018, and taken from the Castle Cliffs viewpoint on the Bow Valley Parkway. The sky was also brightening with dawn twilight blue. This is a stack of 8 exposures for the ground, mean combined to smooth noise, and one exposure for the sky. All 30 seconds at f/2 with the Sigma 24mm Art lens, and Nikon D750 at ISO 3200. LENR dark frame subtraction applied in camera.
